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classification of quarks

The discovery in the 1970s of the “charm” (
c) and “bottom” (
b) quarks and their associated antiquarks, achieved through the creation of mesons, strongly suggests that quarks occur in pairs. This speculation led to efforts to find a sixth type of quark called “top” (
t), after its proposed flavour. According to theory, the top quark carries...

Fermilab discovery

...physicist Leon Lederman, studying the results of 400-GeV proton-nucleus collisions in the original main ring, discovered the first evidence for the upsilon meson, which revealed the existence of the
bottom quark. The
bottom quark, the fifth quark to be detected, is a member of the third and heaviest pair of quarks. The companion particle of this pair is the top quark, which is the sixth and...

relationship to meson

...of charm, a new quantum number the existence of which implies that quarks are related in pairs. The subsequent discovery of another heavy meson, called upsilon, revealed the existence of the
bottom quark and its accompanying antiquark and gave rise to speculation about the existence of a companion particle, the top quark. This sixth quark type, or “flavour,” was discovered in...